Optical lens assembly and method of forming image using the same

ABSTRACT

Provided are an optical lens assembly and a method of forming an image. The optical lens assembly includes: a first lens having a convex object-side surface; a second lens having a convex object-side surface; at least one lens at an image side of the second lens; a first stop being a variable stop at an object side of the first lens; and a second stop at an image side of the first lens, wherein the second stop determines a minimum F number, and the first stop is variable to determine an F number greater than the minimum F number.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Divisional application of U.S. patent applicationSer. No. 15/840,369 filed on Dec. 13, 2017 which claims priority fromthe benefit of Korean Patent Application No. 10-2016-0170414, filed onDec. 14, 2016, in the Korean Intellectual Property Office, thedisclosure of which is incorporated herein in its entirety by reference.

BACKGROUND 1. Field

The present disclosure generally relates to an optical lens assembly anda method of forming an image using the optical lens assembly. Moreparticularly, the present disclosure relates to an optical lens assemblyhaving high resolution under high-illumination conditions and capable offorming bright images under low-illumination conditions, and a method offorming such images using the optical lens assembly.

2. Description of the Related Art

Electronic apparatuses that exist in the art provide various servicesand functions. For example, electronic apparatuses such as mobiledevices or user devices may provide various services using varioussensor modules, and may provide photographic services or video services.Along with the increasing use of electronic apparatuses, the use ofcameras operatively connected to electronic apparatuses has alsogradually increased. This increasing use has caused improvements in theperformance and/or resolution of cameras of electronic apparatuses.Photographs of various landscapes or people, or selfies may be takenusing these cameras of electronic apparatuses. In addition, the capturedphotographs or videos may be shared through social network sites orother media.

For photographing devices that are included in mobile devices, such ascellular phones, laptop computers, tablet personal computers (PC),smartwatches, or drones, users increasingly desire to capture brightimages under low-illumination conditions. Therefore, there is anincreasing need for a lens having short and compact structure forportability, a wide field of view, and a low F number.

SUMMARY

In recent years, there has been large increasing demand for small cameramodules for portable terminals, and along with this, image sensors usedin camera modules, such as a charge-coupled device (CCD) or acomplementary metal oxide semiconductor (CMOS) image sensor, have to bedesigned to have high pixel density. Optical lens assemblies used insmall camera modules of portable terminals are required to have highoptical performance for use with such high pixel image sensors toguarantee high image quality. In the related art, most optical lensassemblies used in small camera modules of portable terminals aregenerally of a fixed stop type having a low F number. Such opticalsystems of a fixed stop type having a low F number make it possible toeffectively improve image brightness under low-illumination conditions,but may have poor resolution under high-illumination conditions becauseof coma aberration.

Various embodiments may provide optical lens assemblies that may beused, for example, in electronic apparatuses (such as portableterminals) to obtain bright images under low-illumination conditions andhigh-resolution images under high-illumination conditions.

In addition, various embodiments may provide methods of forming brightimages under low-illumination conditions and high-resolution imagesunder high-illumination conditions.

Additional aspects will be set forth in part in the description whichfollows and, in part, will be apparent from the description, or may belearned by practice of the presented embodiments.

To solve the above-described problems or other problems, for example, anoptical lens assembly according to an embodiment may include: a firstlens having a convex object-side surface; a second lens having a convexobject-side surface; at least one lens at an image side of the secondlens; a first stop being a variable stop at an object side of the firstlens; and a second stop between an image side of the first stop and theat least one lens at the image side of the second lens, wherein thesecond stop may determine a minimum F number, and the first stop may bevariable to determine an F number greater than the minimum F number,wherein the optical lens assembly may satisfy the following conditions:

$\begin{matrix}{\frac{{d\; 2}}{{{sag}\; 1}} \leq 0.9} & {\text{<}{Conditions}\text{>}} \\{0.2 \leq \frac{R\; 1}{f} \leq 0.8} & \;\end{matrix}$

where sag1 denotes a sag value of the object-side surface of the firstlens measured based on an effective diameter at the minimum F number, d2denotes a distance measured from a vertex of the object-side surface ofthe first lens to the first stop along an optical axis, R1 denotes aradius of curvature of the object-side surface of the first lens, and fdenotes a total focal length of the optical lens assembly.

To solve the above-described problems or other problems, for example, anoptical lens assembly according to an embodiment may include: at leastfive lenses arranged between an object and an image plane; a variablestop provided at an object side of a lens closest to the object amongthe at least five lenses; and a fixed stop provided between an imageside of the variable stop and an image-side surface of a third lens fromthe object, wherein the fixed stop may determine a first F number for amaximum aperture, and the variable stop may be moved to adjust a secondF number greater than the first F number, wherein, during a focusingoperation, the variable stop and the fixed stop may be moved togetherwith the at least five lenses.

To solve the above-described problems or other problems, for example, amethod of forming an image according to an embodiment may be performedusing an optical lens assembly including a plurality of lenses, and themethod may include: allowing a first lens closest to an object among theplurality of lenses to receive light; adjusting a first F number bymoving a first stop provided at an object side of the first lens;determining a second F number for a maximum aperture by using a secondstop provided between an image side of the first stop and an image-sidesurface of a third lens from the object among the plurality of lenses;and adjusting an amount of the received light by using the first andsecond stops.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects will become apparent and more readilyappreciated from the following description of the embodiments, taken inconjunction with the accompanying drawings in which:

FIG. 1 illustrates an optical lens assembly of a first numericalembodiment according to various embodiments;

FIG. 2 illustrates aberration diagrams of the optical lens assembly ofthe first numerical embodiment according to various embodiments;

FIG. 3 illustrates an optical lens assembly of a second numericalembodiment according to various embodiments;

FIG. 4 illustrates aberration diagrams of the optical lens assembly ofthe second numerical embodiment according to various embodiments;

FIG. 5 illustrates a method of forming an image using an optical lensassembly according to various embodiments;

FIG. 6 illustrates an electronic apparatus including an optical lensassembly according to various embodiments;

FIG. 7 illustrates a network environment system according to variousembodiments; and

FIG. 8 illustrates a block diagram illustrating an electronic apparatusaccording to various embodiments.

DETAILED DESCRIPTION

Hereinafter, various embodiments of the present disclosure will bedescribed with reference to the accompanying drawings. However, itshould be understood that there is no intent to limit the presentdisclosure to the particular forms disclosed herein; rather, the presentdisclosure should be construed to cover various modifications,equivalents, and/or alternatives of embodiments. In describing thedrawings, similar reference numerals may be used to designate similarconstituent elements.

As used herein, the expressions “have,” “may have,” “include,” or “mayinclude” refer to the existence of a corresponding feature (e.g.,numeral, function, operation, or constituent element, such ascomponent), and do not exclude one or more additional features.

In the present disclosure, the expressions “A or B,” “at least one of Aand/or B,” and “one or more of A and/or B” may include all possiblecombinations of the items listed. For example, the expressions “A or B,”“at least one of A and B,” or “at least one of A or B” refer to all of(1) including at least A, (2) including at least B, and (3) includingall of at least A and at least B.

Expressions, such as “a first,” “a second,” “the first,” or “thesecond,” used herein may modify various elements regardless of the orderand/or the importance of the elements. Such expressions are used todistinguish one element from other elements, but do not limit thecorresponding elements. For example, a first user device and a seconduser device may indicate different user devices regardless of the orderor importance of the user devices. For example, a first element may bereferred to as a second element, and similarly, a second element may bereferred to as a first element without departing from the scope of thepresent disclosure.

It should be understood that when an element (e.g., first element) isreferred to as being (operatively or communicatively) “coupled,” or“connected,” to another element (e.g., second element), the firstelement may be coupled or connected directly to the second element orany other element (e.g., third element) may be interposed between thetwo elements. In contrast, it may be understood that when an element(e.g., first element) is referred to as being “directly coupled,” or“directly connected” to another element (second element), there are noelement (e.g., third element) interposed between the two elements.

The expression “configured to” used herein may be exchanged with, forexample, “suitable for,” “having the capacity to,” “designed to,”“adapted to,” “made to,” or “capable of” according to the situation. Theexpression “configured to” does not necessarily imply “specificallydesigned to” in hardware. Alternatively, in some situations, theexpression “device configured to” may mean that the device, togetherwith other devices or components, “is able to.” For example, the phrase“processor configured (or adapted) to perform A, B, and C” may refer toa dedicated processor (e.g. an embedded processor) only for performingthe corresponding operations or a generic-purpose processor (e.g., acentral processing unit (CPU) or application processor (AP)) that canperform the corresponding operations by executing one or more softwareprograms stored in a memory device.

Terms used herein are merely for the purpose of describing particularembodiments and are not intended to limit the scope of otherembodiments. As used herein, singular forms may include plural forms aswell unless the context clearly indicates otherwise. Unless definedotherwise, all terms used herein, including technical and scientificterms, have the same meaning as those commonly understood by a personskilled in the art to which the present disclosure pertains. Terms suchas those defined in a generally used dictionary may be interpreted tohave the same meanings as the contextual meanings in the relevant fieldof art, and are not to be interpreted to have excessively formalmeanings unless clearly defined herein. In some cases, even a termdefined in the present disclosure should not be interpreted as a meaningof excluding some embodiments.

An electronic apparatus, according to various embodiments, may includeat least one of a smartphone, a tablet personal computer (PC), a mobilephone, a video phone, an electronic book reader (e-book reader), adesktop PC, a laptop PC, a netbook computer, a workstation, a server, apersonal digital assistant (PDA), a portable multimedia player (PMP), anMPEG-1 audio layer-3 (MP3) player, a mobile medical device, a camera, ora wearable device. According to various embodiments, the wearable devicemay include at least one of an accessory type (e.g., a watch, a ring, abracelet, an anklet, a necklace, glasses, a contact lens, or ahead-mounted device (HMD)), a fabric or clothing integrated type (e.g.,electronic clothing), a body-mounted type (e.g., a skin pad, or tattoo),or a bio-implantable type (e.g., an implantable circuit).

According to some embodiments, the electronic apparatus may be a homeappliance. The home appliance may include at least one of, for example,a television, a digital versatile disk (DVD) player, an audio player, arefrigerator, an air conditioner, a vacuum cleaner, an oven, a microwaveoven, a washing machine, an air cleaner, a set-top box, a homeautomation control panel, a security control panel, a TV box (e.g.,Samsung HomeSync™, Apple TV™, or Google TV™), a game console (e.g.,Xbox™ and PlayStation™), an electronic dictionary, an electronic key, acamcorder, or an electronic photo frame.

According to another embodiment, the electronic apparatus may include atleast one of various medical devices such as portable medical measuringdevices (e.g., a blood glucose monitoring device, a heart ratemonitoring device, a blood pressure measuring device, or a bodytemperature measuring device, a magnetic resonance angiography (MRA)machine, a magnetic resonance imaging (MRI) machine, a computedtomography (CT) machine, or an ultrasonic machine), a navigation device,a global navigation satellite system (GNSS), an event data recorder(EDR), a flight data recorder (FDR), a vehicle infotainment device, anelectronic apparatus for a ship (e.g., a navigation device for a ship,and a gyro-compass), an avionics device, a security device, anautomotive head unit, a robot for home or industry, an automaticteller's machine (ATM), a point of sales (POS) machine, or an Internetof Things (IoT) device (e.g., a light bulb, various sensors, an electricor gas meter, a sprinkler device, a fire alarm, a thermostat, astreetlamp, a toaster, sporting goods, a hot water tank, a heater, aboiler, etc.).

According to some embodiments, the electronic apparatus may include atleast one of a part of furniture or a building/structure, an electronicboard, an electronic signature receiving device, a projector, or variouskinds of measuring instruments (e.g., a water meter, an electric meter,a gas meter, or a radio wave meter). The electronic apparatus, accordingto various embodiments, may be a combination of one or more of theaforementioned various devices. In some embodiments, the electronicapparatus may be a flexible device. Furthermore, the electronicapparatus is not limited to the aforementioned devices, and may includea new electronic apparatus according to the development of newtechniques.

Hereinafter, electronic apparatuses will be described according tovarious embodiments with reference to the accompanying drawings. As usedherein, the term “user” may indicate a person who uses an electronicapparatus or a device (e.g., an artificial intelligence electronicapparatus) that uses an electronic apparatus.

Hereinafter, optical lens assemblies and methods of forming images usingthe optical lens assemblies will be described according to variousembodiments with reference to the accompanying drawings.

FIG. 1 illustrates an optical lens assembly 100-1 of a first numericalembodiment according to various embodiments.

According to various embodiments, the optical lens assembly 100-1 mayinclude a first lens L11, a second lens L21, at least one lens at animage side I of the second lens L21, a first stop ST11 being a variablestop located at an object side O of the first lens L11, and a secondstop ST21 located on an image side I of the first lens L11.

In the following descriptions of lenses, the term “image side” may referto the side located in the direction toward an image plane IMG on whichimages are to be formed, and the term “object side” may refer to theside located in the direction toward an object whose image is to becaptured. In addition, an “object-side surface” of a lens may refer tothe surface of the lens facing the object and may be the left surface orentrance surface of the lens in the drawings, and an “image-sidesurface” of a lens may refer to the surface of the lens facing the imageplane IMG and may be the right surface or exit surface of the lens inthe drawings. For example, the image plane IMG may be a surface of animaging device or an image sensor. For example, the image sensor mayinclude a complementary metal oxide semiconductor (CMOS) image sensor ora sensor such as a charge-coupled device (CCD). However, the imagesensor is not limited thereto. For example, the image sensor may be adevice capable of converting images of objects into electrical imagesignals.

The first lens L11 may have a convex object-side surface 2, and thesecond lens L21 may have a convex object-side surface 4. According tovarious embodiments, the first lens L11 may have positive refractivepower, and the second lens L21 may have positive refractive power. Thefirst lens L11 may have a meniscus shape convex toward the object. Forexample, the second lens L21 may be a biconvex lens. According tovarious embodiments, the at least one lens at the image side I of thesecond lens L21 may include a third lens L31, a fourth lens L41, a fifthlens L51, and a sixth lens L61. For example, the third lens L31 may havenegative refractive power, and the fourth lens L41 may have norefractive power. For example, the third lens L31 may have a meniscusshape convex toward the object. Aberration may be suppressed by placingthe third lens L31 having negative refractive power on the image side Iof the second lens L21.

For example, the fourth lens L41 may have a flat shape in a region ofthe object-side surface 8 near the optical axis OA and a flat shape in aregion of the image-side surface 9 near the optical axis OA. The regionnear the optical axis OA may refer to a region located within apredetermined radius from the optical axis OA. However, the shape of thefourth lens L41 is not limited thereto. The fifth lens L51 may havepositive refractive power, and the sixth lens L61 may have negativerefractive power.

The fifth lens L51 may have at least one inflection point. For example,the fifth lens L51 may have a biconvex shape in a region near theoptical axis OA (for example, a region between the first inflectionpoint and the optical axis OA). For example, the term “inflection point”may refer to a point at which the sign of the radius of curvature of thelens surface changes from positive (+) to negative (−), or from negative(−) to positive (+). Alternatively, the term “reflection point” mayrefer to a point at which the shape of the lens surface changes fromconvex to concave, or from concave to convex. The term “radius ofcurvature” may refer to a value expressing the degree of curvature ateach point of a curve or a curved surface.

The sixth lens L61 may have at least one inflection point on at leastone of the object-side surface 12 and the image-side surface 13. Theobject-side surface 12 of the sixth lens L61 may be convex in a regionnear the optical axis OA and concave away from the optical axis OA. Theimage-side surface 13 of the sixth lens L61 may be concave in a regionnear the optical axis OA and convex away from the optical axis OA. Thesixth lens L61 may have a meniscus shape convex toward the object in aregion near the optical axis OA.

The first stop ST11 may be a variable stop, and the second stop ST21 maybe a fixed stop. According to various embodiments, the second stop ST21may determine the minimum F number of the optical lens assembly 100-1,and the first stop ST11 may be varied to determine an F number greaterthan the minimum F number. The second stop ST21 may determine a first Fnumber for maximum aperture, and the first stop ST11 may be moved toadjust a second F number greater than the first F number. At the minimumF number, that is, in the brightest state of the optical lens assembly100-1, only the second stop ST21 may serve as the stop. In other words,the second stop ST21 may determine the maximum effective diameter of theoptical lens assembly 100-1, and the first stop ST11 may be varied todetermine a diameter smaller than the maximum effective diameter.

According to various embodiments, for example, the optical lens assembly100-1 may be used in a portable terminal and be a large diameter lenssystem having an F number of about 2.0 or less at the maximum aperture.The first stop ST11 functioning as the smaller stop may be located onthe outer side of the optical lens assembly 100-1, and the second stopST21 functioning as the maximum aperture stop may be located inside theoptical lens assembly 100-1. Here, the outer side of the optical lensassembly 100-1 does not refer to a position between lenses of theoptical lens assembly 100-1, but may refer to a position located on theobject side O of the first lens L11 which is closest to the object. Inaddition, the inside of the optical lens assembly 100-1 may refer to aposition between lenses of the optical lens assembly 100-1.

The first stop ST11 may be located at the object side O of the firstlens L11 which is closest to the object. For example, the first stopST11 may be located close to the object-side surface 2 of the first lensL11 to a degree not exceeding the sag value of the object-side surface2. According to various embodiments, the second stop ST21 may be locatedbetween the first lens L11 and the second lens L21. For example, thesecond stop ST21 may be located on the image-side surface 3 of the firstlens L11.

During a focusing operation in which the lenses of the optical lensassembly 100-1 are moved along the optical axis OA so that a focusedimage is incident on the image plane IMG, the first stop ST11 and thesecond stop ST21 may be moved together with the lenses. Therefore, itmay not be necessary to separately include a motor for moving the lensesand a motor for moving the stops. As a result, the optical lens assembly100-1 may have a small size.

According to various embodiments, at least one optical element OF1 maybe between the sixth lens L61 and the image plane IMG. The opticalelement OF1 may include at least one of a low pass filter, an infrared(IR)-cut filter, or cover glass. For example, if the optical element OF1is an IR-cut filter, visible light rays may pass through the opticalelement OF1 but infrared rays may not pass through the optical elementOF1. Thus, infrared rays may not reach the image plane IMG. However, theoptical lens assembly 100-1 may not include the optical element OF1.

According to various embodiments, the optical lens assembly 100-1 mayinclude at least one aspheric lens in order to decrease astigmatic fieldcurvature. For example, all the lenses of the optical lens assembly100-1 may be aspheric lenses. Aspheric lenses having inflection pointsmay decrease astigmatic field curvature.

In addition, according to various embodiments, the optical lens assembly100-1 may include at least one plastic lens. According to variousembodiments, the optical lens assembly 100-1 may include at least threeplastic lenses. For example, all the lenses of the optical lens assembly100-1 may be plastic lenses. As such, the weight of the optical lensassembly 100-1 may be reduced, and manufacturing costs of the opticallens assembly 100-1 may also be reduced.

FIG. 3 illustrates an optical lens assembly 100-2 of a second numericalembodiment according to various embodiments.

According to various embodiments, the optical lens assembly 100-2 mayinclude a first lens L12, a second lens L22, at least one lens at theimage side I of the second lens L22, a first stop ST12 being a variablestop located at the object side O of the first lens L12, and a secondstop ST22 located at the image side I of the first lens L12.

The first lens L12 may have a convex object-side surface 2, and thesecond lens L22 may have a convex object-side surface 4. According tovarious embodiments, the first lens L12 may have positive refractivepower, and the second lens L21 may have positive refractive power. Thefirst lens L12 may have a meniscus shape convex toward the object. Forexample, the second lens L22 may be a biconvex lens. According tovarious embodiments, the at least one lens at the image side I of thesecond lens L22 may include a third lens L32, a fourth lens L42, a fifthlens L52, a sixth lens L62, and a seventh lens L72. For example, thesecond lens L32 may have negative refractive power, and the fourth lensL42 may have positive refractive power. For example, the fifth lens L52may have no refractive power. For example, the fifth lens L52 may have aflat object-side surface 10 and a flat image-side surface 11. In thiscase, the flat object-side surface 10 and the flat image-side surface 11may be flat within the range of the effective diameter of the opticallens assembly 100-2. However, the shape of the fifth lens L52 is notlimited thereto. The sixth lens L62 may have positive refractive power,and the seventh lens L72 may have negative refractive power.

The seventh lens L72 being closest to an image plane IMG may have atleast one inflection point. For example, the object-side surface 14 ofthe seventh lens L72 may be convex in a region near an optical axis OAand concave away from the optical axis OA. The image-side surface 15 ofthe seventh lens L72 may be concave in a region near the optical axis OAand convex away from the optical axis OA. The seventh lens L72 may havea meniscus shape convex toward the object in a region near the opticalaxis OA.

The first stop ST12 may be a variable stop, and the second stop ST22 maybe a fixed stop. The second stop ST22 may determine the maximumeffective diameter of the optical lens assembly 100-2, and the firststop ST12 may be varied to determine a diameter smaller than the maximumeffective diameter. In other words, the second stop ST22 may determine afirst F number for a maximum aperture, and the first stop ST12 may bemoved to adjust a second F number greater than the first F number.

The first stop ST12 may be located at the object side of the first lensL12 and be closest to the object. According to various embodiments, thesecond stop ST22 may be located between the second lens L22 and thethird lens L32. For example, the second stop ST22 may be located on theimage-side surface 6 of the third lens L32.

When the optical lens assembly 100-2 is focused, the first stop ST12 andthe second stop S22 may be moved together with the lenses of the opticallens assembly 100-2. According to various embodiments, at least oneoptical element OF2 may be between the seventh lens L72 and an imageplane IMG.

According to various embodiments, the optical lens assembly 100-2 mayinclude at least one aspheric lens in order to decrease astigmatic fieldcurvature. For example, all the lenses of the optical lens assembly100-2 may be aspheric lenses.

In addition, according to various embodiments, the optical lens assembly100-2 may include at least one plastic lens. For example, all the lensesof the optical lens assembly 100-2 may be plastic lenses.

In the optical lens assemblies of the various embodiments, a variablestop is located at an object side of a lens closest to an object, and amaximum aperture stop is located between lenses, thereby minimizing thesize of the optical lens assembly. If the maximum aperture stop islocated on the outer side of a lens optical system, the lens opticalsystem may have excessive coma aberration. For this reason, according tothe various embodiments, the variable stop serving as the smaller stopis located on the outer side of a lens system, and the fixed stopserving as the maximum aperture stop is located inside the lens system,thereby minimizing the coma aberration.

In addition, according to the various embodiments, when the optical lensassemblies are moved for focusing, the first and second stops are movedtogether with the optical lens assemblies, thereby reducing variationsin peripheral light amount and the aberrations caused by suchvariations. Thus, optical performance may be maintained.

The optical lens assemblies of the various embodiments may satisfy thefollowing conditions. The following conditions will be described withreference to the optical lens assembly 100-1 of the first numericalembodiment. However, the following conditions may be applied to otherembodiments in the same manner.

$\begin{matrix}{\frac{{d\; 2}}{{{sag}\; 1}} \leq 0.9} & {\text{<}{Condition}\mspace{14mu} 1\text{>}} \\{0.2 \leq \frac{R\; 1}{f} \leq 0.8} & {\text{<}{Condition}\mspace{14mu} 2\text{>}}\end{matrix}$

where sag1 denotes the sag value of the object-side surface 2 of thefirst lens L11 measured based on the effective diameter at the minimum Fnumber, d2 denotes the distance measured from the vertex of theobject-side surface 2 of the first lens L11 to the first stop ST11 alongthe optical axis OA, R1 denotes the radius of curvature of theobject-side surface 2 of the first lens L11, and f denotes the totalfocal length of the optical lens assembly 100-1. sag1 may refer to thesag value measured from the effective diameter of the object-sidesurface 2 of the first lens L11 when the second stop ST21 is in amaximally opened state (that is, in the brightest state). In this case,the first stop ST11 is not further restricting the aperture of the lensassembly.

Condition 1 is for preventing the distance from the first stop ST11 tothe object-side surface 2 of the first lens L11 from excessivelyexceeding the sag value of the object-side surface 2 of the first lensL11. If

$\frac{{d\; 2}}{{{sag}\; 1}}$exceeds the upper limit of Condition 1, the first stop ST11 may be toodistant from the object-side surface 2 of the first lens L11 in thedirection toward the image plane IMG, and the first stop ST11 may belocated inside the lens system. In this case, the optical lens assembly100-1 may have a large size, or the first stop ST11 may not be preciselyoperated. Conversely, if the first stop ST11 is distant from theobject-side surface 2 of the first lens L11 in the direction toward theobject by more than the sag value, the optical lens assembly 100-1 mayhave a large size, and thus it may be difficult to decrease the size ofthe optical lens assembly 100-1.

Condition 2 restricts the curvature of the object-side surface 2 of thefirst lens L11. If K1/f exceeds the upper limit of Condition 2, theobject-side surface 2 of the first lens L11 may be too flat. In thiscase, it may be difficult to ensure the sag value for placing the firststop ST11, and the first stop ST11 may have poor efficiency. If K1/f isless than the lower limit of Condition 2, the curvature of theobject-side surface 2 of the first lens L11 may be too large, and therefractive power of the first lens L11 may be excessively high, therebycausing spherical aberration.

The optical lens assemblies of the various embodiments may satisfy thefollowing conditions.

$\begin{matrix}{0.4 < \frac{{Fno}\; 1}{{Fno}\; 2} < 0.8} & {\text{<}{Condition}\mspace{14mu} 3\text{>}}\end{matrix}$

where Fno1 denotes an F number when the second stop ST21 is in amaximally opened state, and Fno2 denotes an F number when the first stopST11 is in a variably opened state.

Condition 3 specifies the ratio of the F number of the second stop ST21in a maximally opened state to the F number of the first stop ST11 beinga small stop. If

$\frac{{Fno}\; 1}{{Fno}\; 2}$exceeds the upper limit of Condition 2, the F number of the maximallyopened stop may increase to cause a decrease in the brightness of imagesunder a low-illumination condition, or the F number of the small stopmay decrease to cause a decrease in the quality of images when the smallstop is opened under a high-illumination condition. If

$\frac{{Fno}\; 1}{{Fno}\; 2}$is less than the lower limit of Condition 3, the F number of themaximally opened stop may decrease to cause a decrease in the field offocus, or the F number of the small stop may increase to cause adecrease in performance because of the diffraction limit.

The optical lens assemblies of the various embodiments may satisfy thefollowing conditions.

$\begin{matrix}{1.0 < \frac{TT}{Y_{IH}} < 1.8} & {\text{<}{Condition}\mspace{14mu} 4\text{>}}\end{matrix}$

where TT denotes a distance from the first stop ST11 to the image sensoralong the optical axis OA, and Y_(IH) denotes half the diagonal lengthof the image sensor.

If

$\frac{TT}{Y_{IH}}$exceeds the upper limit of Condition 4, it is difficult to reduce thesize of the optical lens assembly 100-1. If

$\frac{TT}{Y_{IH}}$is less than the lower limit of Condition 4, the first stop ST11 isexcessively close to the image sensor, and thus it is difficult tocorrect distortion at a wide field of view and reduce the angle ofincidence of rays on the image sensor.

The optical lens assemblies of the various embodiments may satisfy thefollowing conditions.

$\begin{matrix}{0 < \frac{t\; 21}{Y_{IH}} < 1.0} & {\text{<}{Condition}\mspace{14mu} 5\text{>}}\end{matrix}$

where t21 denotes a distance from the first stop ST11 to the second stopST21 along the optical axis OA, and Y_(IH) denotes half the diagonallength of the image sensor.

Condition 5 specifies the ratio of the distance between the first stopST11 and the second stop ST21 to the height of the image plane IMG. If

$\frac{t\; 21}{Y_{IH}}$exceeds the upper limit of Condition 5, the second stop ST21 isexcessively close to the image plane IMG. In this case, peripheral raysmay be excessively blocked, and thus the amount of peripheral light maybe small. If

$\frac{t\; 21}{Y_{IH}}$is less than the lower limit of Condition 5, the second stop ST21 isplaced at the object side of the first stop ST11, and thus, it may bedifficult for the second stop ST21 to correct coma aberration at themaximum aperture.

The optical lens assemblies of the various embodiments may satisfy thefollowing conditions.

$\begin{matrix}{0.1 < \frac{s\; 2}{Y_{IH}} < 0.5} & {\text{<}{Condition}\mspace{14mu} 6\text{>}}\end{matrix}$

where s2 denotes the radius of the first stop ST11 at its maximum Fnumber, and Y_(IH) denotes half the diagonal length of the image sensor.

Condition 6 specifies the ratio of the radius of the first stop ST11 atthe maximum F number of the first stop ST11 to the height of the imageplane IMG. If

$\frac{s\; 2}{Y_{IH}}$exceeds the upper limit of Condition 6, the radius of the first stopST11 may be excessively large, and thus the F number of the first stopST11 may be excessively low. In this case, when the first stop ST11 isopened, the quality of images may decrease. If

$\frac{s\; 2}{Y_{IH}}$is less than the lower limit of Condition 6, the radius of the firststop ST11 may be excessively small, and thus the F number of the firststop ST11 may be excessively large. In this case, optical performancemay be lowered due to the diffraction limit.

The optical lens assemblies of the various embodiments may satisfy thefollowing conditions.

$\begin{matrix}{0.4 < \frac{f}{f\; 2} < 1.6} & {\text{<}{Condition}\mspace{14mu} 7\text{>}}\end{matrix}$

where f denotes the total focal length of the optical lens assembly100-1, and f2 denotes the focal length of the second lens L21.

If

$\frac{f}{f\; 2}$exceeds the upper limit of Condition 7, the refractive power of thesecond lens L21 may be excessively high, making it difficult to correctaberration. If

$\frac{f}{f\; 2}$is less than the lower limit of Condition 7, the refractive power of thesecond lens L21 may be excessively low, making it difficult to reducethe size of the camera module.

When the optical lens assembly of any one of the various embodiments isfocused to compensate for variations in the image plane caused byvariations in the distance from an object, the entire lens system may bemoved, and the first and second stops may be moved together with thelens system. If a lens system and a stop are moved together as describedabove, variations in the amount of peripheral light and coma aberrationmay be reduced, and thus deterioration of optical performance may bereduced.

In the descriptions of the optical lens assemblies of the variousembodiments, the term “aspheric” or “aspheric surface” has the followingdefinition.

When an optical axis is set as a z-axis, a direction perpendicular tothe optical axis is set as a y-axis, and the propagation direction ofrays is denoted as a positive direction, an aspheric surface of a lensmay be defined by the following condition 8. In Condition 8, z denotes adistance measured from the vertex of the lens in the direction of theoptical axis of the lens, y denotes a distance measured from the opticalaxis in a direction perpendicular to the optical axis, K denotes a conicconstant, A, B, C, D, . . . denote aspheric coefficients, and c denotesthe reciprocal (1/R) of the radius of curvature at the vertex of thelens.

$\begin{matrix}{z = {\frac{{cy}^{2}}{1 + \sqrt{1 - {\left( {K + 1} \right)c^{2}y^{2}}}} + {Ay}^{4} + {By}^{6} + {Cy}^{8} + {Dy}^{10} + \ldots}} & {\;{\text{<}{Condition}\mspace{14mu} 8\text{>}}}\end{matrix}$

In the present disclosure, various optical lens assemblies may beimplemented according to numerical embodiments as described below.

In the following numerical embodiments, lens surfaces are sequentiallynumbered with 1, 2, 3, . . . , n in the direction from the object to theimage plane IMG where n is a positive integer. In addition, f refers tothe focal length of an optical lens assembly, Fno refers to F-number, 2ωrefers to field of view, R refers to radius of curvature, do refers tolens thickness or air gap between lenses, Nd refers to refractive index,and Vd refers to Abbe number. obj refers to the object, and H-Ape refersto effective diameter. * refers to aspheric surface.

First Numerical Embodiment

FIG. 1 illustrates the optical lens assembly 100-1 of the firstnumerical embodiment according to various embodiments, and, for example,Table 1 shows design data of the first numerical embodiment.

f: 4.20 mm, 2w: 78.02°, d2: 0.1 mm, sag1: 0.28 mm, Fno1: 1.56, Fno2:2.88

TT: 5.4 mm, Y_(IH): 3.5 mm, t21: 0.318 mm

TABLE 1 Lens Surfaces R dn nd vd H-Ape f obj infinity infinity ST11infinity −0.1 D1 2* 2.423 0.418 1.5441 56.09 1.38 10.7123 ST21(3)* 3.8820.231 1.32 4* 3.016 0.722 1.5441 56.09 1.31 3.8366 5* −6.297 0.02 1.286* 9.787 0.24 1.65038 21.52 1.20 −5.4437 7* 2.595 0.486 1.18 8* infinity0.364 1.65038 21.52 1.30 infinity 9* infinity 0.326 1.47 10*  5.2310.941 1.5441 56.09 1.71 4.7373 11*  −4.8 0.132 2.30 12*  3.779 0.5071.5348 55.71 2.69 −3.3637 13*  1.165 0.263 3.04 14  infinity 0.11 1.516864.20 3.17 15  infinity 0.64 3.20 IMG

Table 2 shows aspheric coefficients in the first numerical embodiment.

TABLE 2 Lens Surfaces K(Conic) A(4th) B(6th) C(8th) D(10th) 2 −2.23959−0.01513 −0.00429 0.00307 −0.02309 3 −2.39313 −0.06386 0.021238 −0.06130.149848 4 1.651358 −0.05725 0.072616 −0.29423 0.708346 5 19.599250.000861 −0.08507 0.258418 −0.54178 6 −19.7524 −0.04651 0.046943−0.11376 0.14405 7 −8.15679 0.020114 −0.00229 0.062001 −0.2526 8 −1−0.03387 −0.0338 −0.06241 0.559919 9 −1 −0.01662 −0.22083 0.43582−0.51131 10 7.812542 0.091594 −0.23064 0.196172 −0.08054 11 2.8288660.258111 −0.2315 0.139869 −0.06535 12 −1.3115 −0.14453 0.044658 −0.008760.001607 13 −5.0663 −0.11044 0.059606 −0.02659 0.007994 Lens SurfacesE(12th) F(14th) G(16th) H(18th) J(20th) 2 0.046025 −0.04951 0.030577−0.00981 0.001249 3 −0.18243 0.121795 −0.0408 0.004922 0.000171 4−0.98125 0.824201 −0.41378 0.114055 −0.01333 5 0.77387 −0.70831 0.395735−0.12262 0.016131 6 −0.05533 −0.0614 0.086325 −0.04092 0.007127 70.491632 −0.55745 0.380021 −0.14384 0.023186 8 −1.16989 1.251872−0.75688 0.246963 −0.03407 9 0.421504 −0.24644 0.097261 −0.0227 0.00229910 −0.03168 0.058068 −0.03069 0.007526 −0.00072 11 0.022228 −0.005180.000768 −6.46E−05   2.33E−06 12 −0.00028 3.58E−05 −2.94E−06 1.35E−07−2.61E−09 13 −0.00149 0.000172 −1.18E−05 4.49E−07 −7.22E−09

Table 3 shows F numbers in the first numerical embodiment.

TABLE 3 Fno when second stop is maximally opened Fno of first stop D11.5 0.73

FIG. 2 illustrates longitudinal spherical aberration, astigmatic fieldcurves, and distortion of the optical lens assembly 100-1 of the firstnumerical embodiment. For example, the longitudinal spherical aberrationwas measured with light having wavelengths of 656.2725 nanometers (NM),587.5618 NM, 546.07400 NM, 486.1327 NM, and 435.8343 NM, and theastigmatic field curves include a tangential field curvature T and asagittal field curvature S. The astigmatic field curves were measuredwith light having wavelengths of 587.5618 NM, and the distortion wasmeasured with light having a wavelength of 587.5618 NM.

Second Numerical Embodiment

FIG. 3 illustrates the optical lens assembly 100-2 of the secondnumerical embodiment according to various embodiments, and, for example,Table 2 shows design data of the second numerical embodiment.

f: 4.34 mm, 2w: 75.85°, d2: 0.15 mm, sag1: 0.52 mm, Fno1: 1.57, Fno2:2.71

TT: 5.27 mm, Y_(IH): 3.5 mm, t21: 1.076 mm

TABLE 4 Lens Surfaces R dn nd vd H-Ape f obj infinity infinity ST12infinity −0.15 D1 2* 2.103 0.533 1.5441 56.09 1.53 9.5054 3* 3.217 0.051.37 4* 2.782 0.613 1.5441 56.09 1.31 4.7142 5* −32.133 0.03 1.25ST22(6)* 6.266 0.24 1.65038 21.52 1.18 −5.3975 7* 2.231 0.252 1.06 8*4.519 0.335 1.5441 56.09 1.06 13.0323 9* 12.04 0.355 1.17 10*  infinity0.31 1.65038 21.52 1.38 infinity 11*  infinity 0.325 1.58 12*  7.2020.635 1.61442 25.95 1.66 14.3596 13*  36.418 0.203 2.20 14*  2.617 0.4751.5348 55.71 2.52 −5.6679 15*  1.318 0.164 2.86 16  infinity 0.11 1.516864.20 3.14 infinity 17  infinity 0.64 3.18 img

Table 5 shows aspheric coefficients in the second numerical embodiment.

TABLE 5 Lens Surfaces K(Conic) A(4th) B(6th) C(8th) D(10th) 2 −0.73267−0.00909 0.021364 −0.06406 0.103376 3 0.179035 0.00398 −0.10025 0.265273−0.5396 4 −1.30187 0.033019 −0.06214 0.153863 −0.33458 5 −67.25860.026722 0.183577 −0.61705 0.836905 6 22.52146 −0.12277 0.502914−1.42405 2.374521 7 −9.60916 −0.02902 0.217672 −0.50194 0.625737 8−89.1585 0.115271 −0.56762 2.506988 −7.69436 9 73.74072 −0.027990.023716 −0.2201 0.747559 10 −1 −0.00855 −0.27937 0.699821 −1.01349 11−1 −0.00736 −0.27799 0.49354 −0.49802 12 13.46983 0.064712 −0.210070.14912 −0.04812 13 46.93376 0.072975 −0.09117 0.032167 −0.00526 14−26.5656 −0.20449 0.102554 −0.04637 0.018601 15 −6.55541 −0.148470.090872 −0.05014 0.02055 Lens Surfaces E(12th) F(14th) G(16th) H(18th)J(20th) 2 −0.1089 0.071644 −0.0281 0.006051 −0.00055 3 0.646915 −0.446550.176888 −0.03713 0.003151 4 0.390796 −0.237 0.070145 −0.00674 −0.000555 −0.59101 0.182645 0.017116 −0.02635 0.004924 6 −2.45717 1.601386−0.64269 0.14713 −0.01526 7 −0.1417 −0.59928 0.779712 −0.40193 0.0798878 14.92814 −18.097 13.28673 −5.40018 0.933669 9 −1.47642 1.709373−1.15214 0.418776 −0.06245 10 0.889278 −0.4716 0.143811 −0.022330.001318 11 0.309307 −0.11217 0.021628 −0.00176  1.69E−05 12 −0.027230.040265 −0.01983 0.004563 −0.00041 13 0.00048 −0.00011  2.76E−05−3.05E−06   1.16E−07 14 −0.00508 0.000869 −9.00E−05 5.18E−06 −1.28E−0715 −0.00561 0.000969 −0.0001 5.76E−06 −1.38E−07

Table 6 shows F numbers in the second numerical embodiment.

TABLE 6 Fno of second stop at maximum aperture Fno of first stop D1 1.80.8

FIG. 4 illustrates longitudinal spherical aberration, astigmatic fieldcurves, and distortion of the optical lens assembly 100-2 of the secondnumerical embodiment.

Table 7 shows that the optical lens assemblies of the variousembodiments satisfy Conditions 1 to 7.

TABLE 7 Embodiment 1 Embodiment 2 Condition 1 0.357 0.288 Condition 20.577 0.485 Condition 3 0.542 0.579 Condition 4 1.514 1.463 Condition 50.091 0.307 Condition 6 0.209 0.229 Condition 7 1.095 0.921

FIG. 5 is a high-level flowchart 1100 for explaining a method of formingan image using any one of the optical lens assemblies of the variousembodiments described with reference to FIGS. 1 to 4.

According to an embodiment, in operation 1101, for example, the firstlens of the optical lens assembly closest to an object may receivelight. In operation 1102, for example, the first stop located at theobject side of the first lens may be moved to adjust the first F number.The first stop may be a variable stop functioning as the smaller stop.In operation 1103, for example, the second stop located at the imageside of the first lens may determine a second F number for maximumaperture. The second stop may be a fixed stop determining the maximumaperture of the optical lens assembly. The second stop may be betweenthe first lens and an image plane.

In operation 1104, for example, the amount of light in the optical lensassembly may be adjusted using the first and second stops according tovarious embodiments. According to various embodiments, when forming animage, the amount of light may be maximized under low-illuminationconditions by using the second stop determining the F number for themaximum aperture so as to obtain bright images, and the first stopdetermining the F number of the smaller stop may be used so as to obtainhigh-resolution images under high-illumination conditions.

For example, the optical lens assemblies of the various embodiments maybe used in electronic apparatuses employing imaging devices. The opticallens assemblies of the various embodiments may be applied to variouselectronic apparatuses such as digital cameras, interchangeable lenscameras, video cameras, smartphone cameras, or cameras of small mobiledevices.

FIG. 6 illustrates an electronic apparatus MG including an optical lensassembly 100 according to an embodiment. FIG. 6 illustrates anon-limiting example where the electronic apparatus MG is a mobilephone. The electronic apparatus MG may include: at least one opticallens assembly 100; and an image sensor 110 configured to receive imagesformed by the at least one optical lens assembly 100 and convert theimages into electric image signals. The optical lens assembly 100 may beany one of the optical lens assemblies described with reference to FIGS.1 to 4. If the optical lens assemblies of the various embodiments areused in photographing apparatuses such as small digital cameras orcameras of mobile phones, the photographing apparatuses may have highphotographing performance.

The image sensor 110 may include infrared-sensitive pixels. Theinfrared-sensitive pixels may enable infrared photographing when it isdifficult to perform visible light photographing, for example, whenindoors or at night. Color filters included in the image sensor 110 maytransmit wavelengths of light corresponding to red, green, and blue, andinfrared wavelengths as well. Therefore, if infrared wavelengths are notblocked, the infrared wavelengths may generate noise in the imagegenerated from visible light. Accordingly, infrared rays may be blockedusing an additional filter or coating. In some embodiments, aninfrared-cut film may be between a first lens group and a second lensgroup at a position where the diameter of a light beam is small, and theinfrared-cut film may be moved using an actuator. Thus, the actuator maymove the infrared-cut film may be outside the optical path whenreception of infrared light is desired. When visible light photographingis performed using the image sensor 110 having infrared-sensitivepixels, infrared rays may be blocked using the infrared-cut film.Alternatively, infrared noise may be removed using signal processing bya processor instead of using the infrared-cut film. In addition, wheninfrared photographing is performed, the infrared-cut film may be movedoutside the optical path, and infrared images may be obtained using theinfrared-sensitive pixels.

FIG. 7 illustrates an electronic apparatus 201 in a network environment200 according to various embodiments. The electronic apparatus 201 mayinclude a bus 210, a processor 220, a camera module 225, a memory 230,an input/output interface 250, a display 260, and a communicationinterface 270. In some embodiments, at least one of the elements of theelectronic apparatus 201 may be omitted, or the electronic apparatus 201may include another element.

For example, the bus 210 may include a circuit configured to connect theelements 210 to 270 for communication therebetween (for example,transmission of control messages and/or data).

The processor 220 may include one or more of a central processing unit(CPU), an application processor (AP), and a communication processor(CP). For example, the processor 220 may perform calculations or dataprocessing which relates to control and/or communication of at least oneof the other elements of the electronic apparatus 201.

For example, the camera module 225 may take still images and videos.According to an embodiment, the camera module 225 may include at leastone image sensor (for example, a front image sensor or a rear imagesensor), a lens, an image signal processor (ISP), or a flash (forexample, a light-emitting diode (LED) or a xenon lamp). For example, thecamera module 225 may include any one of the optical lens assemblies ofthe various embodiments.

The memory 230 may include a volatile memory and/or a nonvolatilememory. For example, the memory 230 may store instructions or datarelating to at least one of the other elements of the electronicapparatus 201. According to an embodiment, the memory 230 may includesoftware and/or a program 240. For example, the program 240 may includea kernel 241, middleware 243, an application programming interface (API)245, and/or application programs (or applications) 247. At least a partof the kernel 241, the middleware 243, or the API 245 may function as anoperating system (OS).

For example, the kernel 241 may control or manage system resources (suchas the bus 210, the processor 220, or the memory 230) used to executeoperations or functions of the other programs (such as the middleware243, the API 245, or the application programs 247). In addition, thekernel 241 may provide an interface allowing the middleware 243, the API245, or the application programs 247 to access individual elements ofthe electronic apparatus 201, thereby making it possible to control ormanage system resources.

For example, the middleware 243 may function as an intermediary so thatthe API 245 or the application programs 247 may communicate with thekernel 241 for transmission of data therebetween.

In addition, the middleware 243 may process one or more operationrequests from the application programs 247 in the order of priority. Forexample, the middleware 243 may give priority to at least one of theapplication programs 247 such that the at least one of the applicationprograms 247 may use system resources (such as the bus 210, theprocessor 220, or the memory 230) of the electronic apparatus 201. Forexample, the middleware 243 may process the one or more operationrequests from the application programs 247 according to the prioritygiven to at least one of the application programs 247. In this manner,the middleware 243 may perform a scheduling or load-balancing operationrelating to the one or more operation requests.

For example, the API 245 may be an interface through which theapplication programs 247 control functions provided by the kernel 241 orthe middleware 243. For example, the API 245 may include at least oneinterface or function (for example, a command) for file control, windowcontrol, image processing, or text control.

For example, the input/output interface 250 may function as an interfacefor transmitting instructions or data input from a user or anotherexternal device to one or more of the other elements of the electronicapparatus 201. In addition, the input/output interface 250 may transmitinstructions or data received from one or more of the other elements ofthe electronic apparatus 201 to a user or another external device.

For example, the display 260 may include a liquid crystal display (LCD),an LED display, an organic light-emitting diode (OLED) display, amicroelectromechanical system (MEMS) display, or an electronic paperdisplay. For example, the display 260 may display content (such astexts, images, videos, icons, or symbols) for users. The display 260 mayinclude a touch screen. For example, the display 260 may receive aninput through a touch, a gesture, an approaching action, or a hoveringaction by an electronic pen or a user's body part.

For example, the communication interface 270 may enable communicationbetween the electronic apparatus 201 and an external device (forexample, a first external electronic apparatus 202, a second externalelectronic apparatus 204, or a server 206). For example, thecommunication interface 270 may communicate with external devices (forexample, the second external electronic apparatus 204 or the server 206)connected to a network 262 by a wireless communication method or a wiredcommunication method.

For example, the wireless communication method may use a cellularprotocol. For example, the wireless communication method may use atleast one of long-term evolution (LTE), LTE advance (LTE-A), codedivision multiple access (CDMA), wideband CDMA (WCDMA), universal mobiletelecommunications system (UMTS), wireless broadband (WiBro), or globalsystem for mobile communications (GSM). In addition, the wirelesscommunication method may include short-range communication 264. Forexample, the short-range communication 264 may include at least one ofwireless fidelity (WiFi), Bluetooth, near field communication (NFC), orglobal navigation satellite system (GNSS). For example, according toregions or bandwidths, GNSS may include at least one of globalpositioning system (GPS), global navigation satellite system (Glonass),Beidou navigation satellite system (hereinafter referred to as Beidou),or the European global satellite-based navigation system (Galileo). Inthe present disclosure, “GPS” and “GNSS” may be interchangeably used.For example, the wired communication method may use at least one ofuniversal serial bus (USB), high definition multimedia interface (HDMI),recommended standard-232 (RS-232), or plain old telephone service(POTS). For example, the network 262 may include at least one of atelecommunications network, a computer network (such as a local areanetwork (LAN) or a wide area network (WAN)), the Internet, or atelephone network.

Each of the first external electronic apparatus 202 and the secondexternal electronic apparatus 204 may be the same as or different fromthe electronic apparatus 201. According to an embodiment, the server 206may include a group of one or more servers. According to an embodiment,all or some operations of the electronic apparatus 201 may be performedin one or more other electronic apparatuses (such as the first andsecond external electronic apparatuses 202 and 204) or the server 206.According to an embodiment, when the electronic apparatus 201 has toperform a function or service by request or automation, instead of or inaddition to performing the function or service by itself, the electronicapparatus 201 may request the server 206 or other devices (such as thefirst external electronic apparatus 202 or the second externalelectronic apparatus 204) to perform at least a part of the function orservice. The server 206 or other devices (such as the first externalelectronic apparatus 202 or the second external electronic apparatus204) may perform the at least part of the function or service inresponse to the request and may send results thereof to the electronicapparatus 201. The electronic apparatus 201 may intactly use thereceived results or may process the received results so as to implementthe function or service. To this end, for example, cloud computing,distributed computing, or client-server computing technology may beused.

FIG. 8 is a block diagram illustrating an electronic apparatus 301according to various embodiments. The electronic apparatus 301 mayentirely or partially include the electronic apparatus 201 illustratedin FIG. 7. The electronic apparatus 301 may include at least oneprocessor 310 (such as an AP), a communication module 320, a subscriberidentification module 324, a memory 330, a sensor module 340, an inputunit 350, a display 360, an interface 370, an audio module 380, a cameramodule 391, a power management module 395, a battery 396, an indicator397, and a motor 398.

For example, the processor 310 may control many pieces of hardware orsoftware connected to the processor 310 by executing an OS or anapplication program, and may perform data processing and calculations.For example, the processor 310 may be implemented as a system on chip(SoC). According to an embodiment, the processor 310 may include agraphics processing unit (GPU) and/or image signal processor. Theprocessor 310 may include at least one element illustrated in FIG. 8(for example, a cellular module 321). The processor 310 may loadinstructions or data transmitted from at least one of the other elements(such as a nonvolatile memory) on a volatile memory and may process theinstructions or data, and may store various data on the nonvolatilememory.

The structure of the communication module 320 may be the same as orsimilar to the structure of the communication interface 270 illustratedin FIG. 7. For example, the communication module 320 may include thecellular module 321, a WiFi module 323, a Bluetooth module 325, a GNSSmodule 327 (such as a GPS module, a Glonass module, a Beidou module, ora Galileo module), an NFC module 328, and a radio frequency (RF) module329.

For example, the cellular module 321 may provide services such as voicecalling, video calling, text messaging, or Internet connection by usinga communication network. According to an embodiment, the cellular module321 may identify and authenticate the electronic apparatus 301 in acommunication network by using the subscriber identification module 324(for example, a subscriber identification module (SIM) card). Accordingto an embodiment, the cellular module 321 may perform at least one offunctions that the processor 310 may provide. According to anembodiment, the cellular module 321 may include a communicationprocessor (CP).

For example, each of the WiFi module 323, the Bluetooth module 325, theGNSS module 327, and the NFC module 328 may include a processor toprocess received data or data to be transmitted. In some embodiments, atleast one of (for example, two of) the cellular module 321, the WiFimodule 323, the Bluetooth module 325, the GNSS module 327, or the NFCmodule 328 may be included in an integrated chip (IC) or an IC package.

For example, the RF module 329 may transmit and receive communicationsignals (for example, RF signals). For example, the RF module 329 mayinclude a transceiver, a power amp module (PAM), a frequency filter, alow noise amplifier (LNA), or an antenna. In other embodiments, at leastone of the cellular module 321, the WiFi module 323, the Bluetoothmodule 325, the GNSS module 327, or the NFC module 328 may transmit andreceive RF signals using a separate RF module.

For example, the subscriber identifier module 324 may include a SIM cardor an embedded SIM. The subscriber identification module 324 may includeunique identification information (such as an integrated circuit cardidentifier (ICCID)) or subscriber information (such as an internationalmobile subscriber identity (IMSI)).

For example, the memory 330 may include a built-in memory 332 or anexternal memory 334. For example, the built-in memory 332 may include atleast one of a volatile memory such as dynamic random access memory(DRAM), static random access memory (SRAM), or synchronous dynamicrandom access memory (SDRAM); or a nonvolatile memory such as one timeprogrammable read only memory (OTPROM), programmable read only memory(PROM), erasable and programmable read only memory (EPROM), electricallyerasable and programmable read only memory (EEPROM), mask read onlymemory (ROM), flash ROM, a flash memory (for example, a NAND flashmemory or a NOR flash memory), a hard disk drive, or a solid state drive(SSD).

The external memory 334 may include a flash drive and may furtherinclude, for example, a compact flash (CD) card, a secure digital (SD)card, a micro secure digital (Micro-SD) card, a mini secure digital(Mini-SD) card, an extreme digital (xD) card, a multi-media card (MMC),or a memory stick. The external memory 334 may be operatively and/orphysically connected to the electronic apparatus 301 through variousinterfaces.

For example, the sensor module 340 may measure physical quantities ordetect operational states of the electronic apparatus 301, and mayconvert measured or detected information into electric signals. Forexample, the sensor module 340 may include at least one of a gesturesensor 340A, a gyro sensor 340B, an atmospheric pressure sensor 340C, amagnetic sensor 340D, an acceleration sensor 340E, a grip sensor 340F, aproximity sensor 340G, a color sensor 340H (such as a red-green-blue(RGB) sensor), a biometric sensor 340I, a temperature/humidity sensor340J, an illuminance sensor 340K, or an ultraviolet (UV) sensor 340M.Additionally or alternatively, the sensor module 340 may, for example,include an E-nose sensor, an electromyography (EMG) sensor, anelectroencephalogram (EEG) sensor, an electrocardiogram (ECG) sensor, aninfrared (IR) sensor, an iris sensor, and/or a fingerprint sensor. Thesensor module 340 may further include a control circuit configured tocontrol at least one sensor of the sensor module 340. In someembodiments, the electronic apparatus 301 may further include aprocessor as a part of or independently of the processor 310 so as tocontrol the sensor module 340. When the processor 310 is in a sleepmode, the processor 310 may control the sensor module 340.

For example, the input unit 350 may include a touch panel 352, a(digital) pen sensor 354, a key 356, or an ultrasonic input unit 358.For example, the touch panel 352 may use at least one of a capacitivemethod, a resistive method, an infrared method, or an ultrasonic method.In addition, the touch panel 352 may further include a control circuit.The touch panel 352 may further include a tactile layer to provide atactile sense to a user.

For example, the (digital) pen sensor 354 may be a part of the touchpanel 352 or may include a separate sensing sheet. For example, the key356 may include a physical button, an optical key, or a keypad. Theultrasonic input unit 358 may detect ultrasonic waves generated from aninput tool by using a microphone (such as a microphone 388) and maycheck data corresponding to the ultrasonic waves.

The display 360 may include a panel 362, a hologram device 364, or aprojector 366. The structure of the panel 362 may be the same as orsimilar to the structure of the display 260 illustrated in FIG. 7. Forexample, the panel 362 may be flexible, transparent, or wearable. Thepanel 362 and the touch panel 352 may be provided as a single module.According to an embodiment, the panel 362 may include a pressure sensor(or a force sensor) capable of sensing the magnitude of touchingpressure by a user. The pressure sensor may be provided as part of thetouch panel 352, or at least one pressure sensor may be providedseparately from the touch panel 352. The hologram device 364 may displaythree-dimensional images in a space by using interference of light. Theprojector 366 may display images by projecting light onto a screen. Forexample, the screen may be located inside or outside the electronicapparatus 301. According to an embodiment, the display 360 may furtherinclude a control circuit to control the panel 362, the hologram device364, or the projector 366.

For example, the interface 370 may include an HDMI 372, a USB 374, anoptical interface 376, or a D-subminiature (D-sub) 378. For example, theinterface 370 may include the communication interface 270 illustrated inFIG. 7. Additionally or alternatively, the interface 370 may, forexample, include a mobile high-definition link (MI-IL) interface, an SDcard/MMC interface, or an infrared data association (IrDA) interface.

For example, the audio module 380 may convert sounds into electricsignals, and electric signals into sounds. For example, at least oneelement of the audio module 380 may include the input/output interface250 illustrated in FIG. 7. For example, the audio module 380 may processsound information that is input through or will be output through aspeaker 382, a receiver 384, earphones 386, or the microphone 388.

For example, the camera module 391 may take still images and videos.According to an embodiment, the camera module 391 may include at leastone image sensor (for example, a front image sensor or a rear imagesensor), a lens, an ISP, or a flash (for example, an LED or a xenonlamp). For example, the camera module 391 may include any one of theoptical lens assemblies of the various embodiments.

For example, the power management module 395 may manage power of theelectronic apparatus 301. The electronic apparatus 301 may receive powerfrom the battery 396. However, the electronic apparatus 301 is notlimited to receiving power from the battery 396. According to anembodiment, the power management module 395 may include a powermanagement integrated circuit (PMIC), a charger integrated circuit (IC),or a battery or fuel gauge. The PMIC may use a wired and/or wirelesscharging method. For example, the wireless charging method may include amagnetic resonance method, a magnetic induction method, or anelectromagnetic wave method, and an additional wireless charging circuitsuch as a coil loop, a resonance circuit, or a rectifier may be used.For example, the battery or fuel gauge may measure the amount ofelectricity remaining in the battery 396 and the voltage, current, ortemperature of the battery 396 during a charging operation. For example,the battery 396 may include a rechargeable battery and/or a solarbattery.

The indicator 397 may display a particular state such as a bootingstate, a messaging state, or a charge state of the electronic apparatus301 or a part of the electronic apparatus 301 (such as the processor310). The motor 398 may convert an electric signal into a mechanicalvibration and may produce a vibrational or haptic effect. The electronicapparatus 301 may include a processing device (such as a GPU) to supporta mobile TV service. The processing unit for a mobile TV service mayprocess media data according to a standard such as digital multimediabroadcasting (DMB), digital video broadcasting (DVB), or mediaFlo™.

According to various embodiments, an optical lens assembly includes: afirst lens having a convex object-side surface; a second lens having aconvex object-side surface; at least one lens at an image side of thesecond lens; a first stop being a variable stop at an object side of thefirst lens; and a second stop between an image side of the first stopand the at least one lens at the image side of the second lens, whereinthe second stop determines a minimum F number, and the first stop isvariable to determine an F number greater than the minimum F number,wherein the optical lens assembly satisfies the following conditions:

$\begin{matrix}{\frac{{d\; 2}}{{{sag}\; 1}} \leq 0.9} & {\;{\text{<}{Conditions}\text{>}}} \\{0.2 \leq \frac{R\; 1}{f} \leq 0.8} & \;\end{matrix}$

where sag1 denotes a sag value of the object-side surface of the firstlens measured based on an effective diameter at the minimum F number, d2denotes a distance measured from a vertex of the object-side surface ofthe first lens to the first stop along an optical axis, R1 denotes aradius of curvature of the object-side surface of the first lens, and fdenotes a total focal length of the optical lens assembly.

For example, the optical lens assembly may satisfy the followingcondition:

$\begin{matrix}{0.4 < \frac{{Fno}\; 1}{{Fno}\; 2} < 0.8} & {\;{\text{<}{Condition}\text{>}}}\end{matrix}$

where Fno1 denotes the minimum F number of the second stop, and Fno2denotes an F number when the first stop is in a variably opened state.

For example, the optical lens assembly may further include an imagesensor, wherein the optical lens assembly may satisfy the followingcondition:

$\begin{matrix}{1.0 < \frac{TT}{Y_{IH}} < 1.8} & {\;{\text{<}{Condition}\text{>}}}\end{matrix}$

where TT denotes a distance from the first stop to the image sensoralong the optical axis, and Y_(IH) denotes half a diagonal length of theimage sensor.

For example, the optical lens assembly may further include an imagesensor, wherein the optical lens assembly may satisfy the followingcondition:

$\begin{matrix}{0 < \frac{t\; 21}{Y_{IH}} < 1.0} & {\;{\text{<}{Condition}\text{>}}}\end{matrix}$

where t21 denotes a distance from the first stop to the second stopalong the optical axis, and Y_(IH) denotes half a diagonal length of theimage sensor.

For example, the optical lens assembly may further include an imagesensor, wherein the optical lens assembly may satisfy the followingcondition:

$\begin{matrix}{0.1 < \frac{s\; 2}{Y_{IH}} < 0.5} & {\;{\text{<}{Condition}\text{>}}}\end{matrix}$

where s2 denotes a radius of the first stop at its maximum F number, andY_(IH) denotes half a diagonal length of the image sensor.

For example, the optical lens assembly may satisfy the followingcondition:

$\begin{matrix}{0.4 < \frac{f}{f\; 2} < 1.6} & {\;{\text{<}{Condition}\text{>}}}\end{matrix}$

where f2 denotes a focal length of the second lens.

For example, the optical lens assembly may further include a third lensat the image side of the second lens, and the third lens may havenegative refractive power and a concave image-side surface.

For example, the optical lens assembly may include at least threeaspheric plastic lenses.

For example, the optical lens assembly may include at least one asphericlens having at least one inflection point.

For example, the first lens may have a positive refractive power.

For example, the first lens may have a meniscus shape.

For example, when the optical lens assembly is focused, the first stopand the second stop may be moved together with the first lens, thesecond lens, and the at least one lens at the image side of the secondlens.

For example, the second stop may be provided between the first lens andthe second lens or provided at the image side of the second lens.

According to various embodiments, an optical lens assembly may include:at least five lenses arranged between an object and an image plane; avariable stop provided at an object side of a lens closest to the objectamong the at least five lenses; and a fixed stop provided between animage side of the variable stop and an image-side surface of a thirdlens from the object, wherein the fixed stop may determine a first Fnumber for a maximum aperture, and the variable stop may be moved toadjust a second F number greater than the first F number, wherein,during a focusing operation, the variable stop and the fixed stop may bemoved together with the at least five lenses.

According to various embodiments, a method of forming an image using anoptical lens assembly including a plurality of lenses may include:allowing a first lens closest to an object among the plurality of lensesto receive light; adjusting a first F number by moving a first stopprovided at an object side of the first lens; determining a second Fnumber for a maximum aperture by using a second stop provided between animage side of the first stop and an image-side surface of a third lensfrom the object among the plurality of lenses; and adjusting an amountof the received light by using the first and second stops.

For example, the first stop may be a variable stop, and the second stopmay be a fixed stop.

For example, when the optical lens assembly is focused, the first andsecond stops may be moved together with the plurality of lenses.

In the present disclosure, each of the above-described elements may beconfigured with one or more components, and the names of the elementsmay vary based on the types of electronic apparatuses. According toembodiments, the electronic apparatus may include at least one of theaforementioned elements. Some elements may be omitted or otheradditional elements may be further included in the electronic apparatus.Furthermore, in some embodiments, some elements of the electronicapparatus may be combined as one entity, which may have the samefunctions as those of the elements.

The term “module” used in this disclosure may refer to a unit including,for example, one of hardware, software, firmware or any combinationthereof. For example, the term “module” may be interchangeable with aterm such as unit, logic, logical block, component, or circuit. A modulemay be formed mechanically or electronically. For example, a module mayinclude at least one of a application-specific integrated circuit (ASIC)chip, a field-programmable gate array (FPGAs), or a programmable-logicdevice which have been known or are to be developed.

According to an embodiment, at least a portion of an apparatus (e.g.,modules or functions thereof) or a method (e.g., operations), forexample, may be implemented as instructions stored in acomputer-readable storage medium in the form of a programmable module.When the instructions are executed by one or more processors (e.g., theprocessor 220 illustrated in FIG. 7), the one or more processors mayperform functions corresponding to the instructions. Thecomputer-readable storage medium, for example, may be the memory 230.

A computer-readable recording medium may include a hard disk, a floppydisk, a magnetic medium (e.g., a magnetic tape), an optical medium(e.g., a compact disc read only memory (CD-ROM), a digital versatiledisc (DVD), a magneto-optical media (e.g., a floptical disk), and ahardware device (e.g., read only memory (ROM), random access memory(RAM), or flash memory). Also, a program instruction may include notonly machine language code such as those generated by a compiler butalso high-level language code executable on a computer using aninterpreter, etc. The above-mentioned hardware device may be configuredto operate via one or more software modules to perform operationsaccording to embodiments, and vice versa. A module or a programmingmodule according to an embodiment may include at least one of theabove-described elements, or a portion of the above-described elementsmay be omitted, or additional other elements may be further included.Operations performed by a module, a programming module, or otherelements according to an embodiment of the present disclosure may beexecuted sequentially, in parallel, repeatedly, or in a heuristicmethod. Also, some operations may be executed in different sequences ormay be omitted, or other operations may be added. It should beunderstood that embodiments described herein should be considered in adescriptive sense only and not for purposes of limitation. Descriptionsof features or aspects within each embodiment should typically beconsidered as available for other similar features or aspects in otherembodiments.

While one or more embodiments have been described with reference to thefigures, it will be understood by those of ordinary skill in the artthat various changes in form and details may be made therein withoutdeparting from the spirit and scope as defined by the following claims.

What is claimed is:
 1. An optical lens assembly comprising: at leastfive lenses arranged between an object and an image plane; a variablestop provided at an object side of a lens closest to the object amongthe at least five lenses; and a fixed stop provided between an imageside of the variable stop and an image-side surface of a third lens fromthe object, wherein the fixed stop determines a first F number for amaximum aperture, and the variable stop is moved to adjust a second Fnumber greater than the first F number, wherein, during a focusingoperation, the variable stop and the fixed stop are moved together withthe at least five lenses.
 2. The optical lens assembly of claim 1,wherein the optical lens assembly satisfies the following condition:$\begin{matrix}{0.4 < \frac{{Fno}\; 1}{{Fno}\; 2} < 0.8} & \left\langle {Condition} \right\rangle\end{matrix}$ where Fno1 denotes the first F number determined by thefixed stop, and Fno2 denotes the second F number determined by thevariable stop.
 3. The optical lens assembly of claim 1, furthercomprising an image sensor, wherein the optical lens assembly satisfiesthe following condition: $\begin{matrix}{0 < \frac{t\; 21}{Y_{IH}} < 1.0} & \left\langle {Condition} \right\rangle\end{matrix}$ where t21 denotes a distance from the variable stop to thefixed stop along an optical axis, and Y_(IH) denotes half a diagonallength of the image sensor.
 4. A method of forming an image using anoptical lens assembly comprising a plurality of lenses, the methodcomprising: allowing a first lens closest to an object among theplurality of lenses to receive light; adjusting a first F number bymoving a first stop provided at an object side of the first lens;determining a second F number for a maximum aperture by using a secondstop provided between an image side of the first stop and an image-sidesurface of a third lens from the object among the plurality of lenses;and adjusting an amount of the received light by using the first andsecond stops, wherein when the optical lens assembly is focused, thefirst and second stops are moved together with the plurality of lenses.5. The method of claim 4, wherein the first stop is a variable stop, andthe second stop is a fixed stop.
 6. The method of claim 4, wherein theoptical lens assembly satisfies the following condition:0.4<Fno1/Fno2<0.8  <Condition> where Fno1 denotes the first F numberdetermined by the first stop, and Fno2 denotes the second F numberdetermined by the second stop.